- From: Pierre-Anthony Lemieux <pal@sandflow.com>
- Date: Mon, 12 Dec 2016 17:43:20 -0800
- To: Glenn Adams <glenn@skynav.com>
- Cc: "public-tt@w3.org" <public-tt@w3.org>
> have you tried a combination of {min,max}-width on the span No. How would it work? > you probably should include references to these examples in your message to CSS; let's see what input they might have Ok. On Mon, Dec 12, 2016 at 5:26 PM, Glenn Adams <glenn@skynav.com> wrote: > > > On Mon, Dec 12, 2016 at 6:11 PM, Pierre-Anthony Lemieux <pal@sandflow.com> > wrote: >> >> Hi Glenn, >> >> > since both of the examples you give, multiRowAlign and linePadding >> >are in fact supported (semantically) by CSS. >> >> I am not so sure. >> >> >display: inline-block on span to obtain multiRowAlign semantics >> >> I have not found a way to make this work without explicit <br> >> elements -- see [1]. >> >> [1] https://codepen.io/palemieux/pen/yVxZWm > > > have you tried a combination of {min,max}-width on the span > >> >> >> >> >use box-decoration-break: clone to obtain linePadding semantics. >> >> I have not found a way to make this work if nested spans are used -- >> see [2] for HTML and attached for TTML. Specifically, linePadding >> requires that the background of the first/last character of each line >> be extended. >> >> - "box-decoration-break: clone" extends the background of the <span> >> at the end of each line, so the background of both outer and inner >> spans are extended. >> >> - CSS padding adds padding to both left and right of a span, >> introducing additional spaces in the text >> >> [2] https://codepen.io/palemieux/pen/vyzbqW >> >> Perhaps you see another way. I would love to be proven wrong! > > > hmm, you may have a counterexample here > > you probably should include references to these examples in your message to > CSS; let's see what input they might have > >> >> >> Best, >> >> -- Pierre >> >> On Mon, Dec 12, 2016 at 4:12 PM, Glenn Adams <glenn@skynav.com> wrote: >> > You are likely to receive pushback on your email, since both of the >> > examples >> > you give, multiRowAlign and linePadding, are in fact supported >> > (semantically) by CSS. >> > >> > Use display: inline-block on span to obtain multiRowAlign semantics and >> > use >> > box-decoration-break: clone to obtain linePadding semantics. >> > >> > As far as I know, none of TTML1 or IMSC1 presentation semantics is not >> > supported by some CSS mapping (whether simple or complex), but that >> > doesn't >> > hold for TTML2, where there are indeed some semantic gaps in CSS. >> > >> > On Mon, Dec 12, 2016 at 3:21 PM, Pierre-Anthony Lemieux >> > <pal@sandflow.com> >> > wrote: >> >> >> >> FYI. My input to the www-style list re: TTML and CSS. >> >> >> >> Best, >> >> >> >> -- Pierre >> >> >> >> >> >> ---------- Forwarded message ---------- >> >> From: Pierre-Anthony Lemieux <pal@sandflow.com> >> >> Date: Sun, Dec 11, 2016 at 9:04 PM >> >> Subject: Subtitle/caption styling + TTML + CSS >> >> To: "L. David Baron" <dbaron@dbaron.org> >> >> Cc: Thierry MICHEL <tmichel@w3.org>, Bert Bos <bert@w3.org>, Chris >> >> Lilley <chris@w3.org>, www-style list <www-style@w3.org>, Nigel Megitt >> >> <nigel.megitt@bbc.co.uk> >> >> >> >> >> >> Hi David et al., >> >> >> >> > I don't think TTML1 was designed in a >> >> > way that would fit well in browser implementations. >> >> >> >> I have been working on an open source JavaScript library [1] for >> >> rendering TTML1 documents to HTML5 fragments. >> >> >> >> [1] https://github.com/sandflow/imscJS >> >> >> >> TTML is based on XSL, which is based on CSS, and so the mapping has >> >> been straightforward. [ed.: I am not sure what you mean by "does not >> >> fit well", perhaps you can elaborate.] >> >> >> >> The most significant challenge has been supporting two features >> >> (linePadding and multiRowAlign [2]), which are not supported in CSS, >> >> but have been identified as essential to captioning in Europe by the >> >> TTWG (and EBU). >> >> >> >> [2] https://www.w3.org/TR/ttml-imsc1/#linepadding >> >> >> >> I would think that features that are important to >> >> subtitling/captioning should be considered for CSS, regardless of the >> >> ultimate timed text format (TTML, WebVTT, etc...) >> >> >> >> Best, >> >> >> >> -- Pierre >> >> >> >> On Wed, Nov 23, 2016 at 3:33 PM, L. David Baron <dbaron@dbaron.org> >> >> wrote: >> >> > On Friday 2016-11-18 17:48 +0100, Thierry MICHEL wrote: >> >> >> CSS colleagues, >> >> >> >> >> >> The Timed Text Working Group (TTWG) published yesterday an ordinary >> >> >> Working >> >> >> Draft of Timed Text Markup Language 2 (TTML2) >> >> >> W3C Working Draft 17 November 2016 >> >> >> https://www.w3.org/TR/2016/WD-ttml2-20161117/ >> >> >> >> >> >> FYI, this publication is not the last publication before requesting >> >> >> transition to Candidate Recommendation. The TTWG plans to publish a >> >> >> final WD >> >> >> soon. We will let you know. >> >> >> >> >> >> Meanwhile, the TTWG invites you to review this TTML2 WD. >> >> >> >> >> >> The horizontal review should focus only on the new features >> >> >> introduced in TTML2. >> >> >> Please refer to the section for changes between Timed Text Markup >> >> >> Language >> >> >> (TTML) Version 1 (TTML1) and Version 2 (TTML2). >> >> >> >> >> >> >> >> >> https://www.w3.org/TR/2016/WD-ttml2-20161117/#changes-from-ttml1-vocabulary >> >> >> >> >> >> Please send your comments to TTWG Public mailing list >> >> >> <public-tt@w3.org>. >> >> > >> >> > So it's worth noting that the styling section of the draft: >> >> > https://w3c.github.io/ttml2/spec/ttml2.html#styling >> >> > has considerable new additions relative to TTML1. This section >> >> > contains a vocabulary that is rather similar to many CSS properties, >> >> > but also contains significant divergence. >> >> > >> >> > In particular, TTML1 had in >> >> > https://www.w3.org/TR/ttaf1-dfxp/#styling-attribute-vocabulary >> >> > the following styling attributes that appear to match CSS at first >> >> > glance, at least in semantics: >> >> > backgroundColor >> >> > color >> >> > direction >> >> > display (only auto vs. none) >> >> > extent (a shorthand for width and height) >> >> > fontFamily >> >> > fontSize >> >> > fontStyle >> >> > fontWeight >> >> > lineHeight >> >> > opacity >> >> > overflow >> >> > padding >> >> > textAlign >> >> > textDecoration (but with extra values) >> >> > unicodeBidi >> >> > visibility >> >> > wrapOption (like text-wrap in css-text-4) >> >> > writingMode (but using old values) >> >> > zIndex >> >> > and the following styling attributes that do not match CSS: >> >> > displayAlign >> >> > origin (a bit like x and y in SVG) >> >> > showBackground >> >> > textOutline >> >> > >> >> > TTML2 introduces the following new properties that appear to have >> >> > similar CSS properties at first glance: >> >> > backgroundClip (with different names for the values) >> >> > backgroundExtent (equivalent to background-size) >> >> > backgroundImage >> >> > backgroundOrigin (with different names for the values) >> >> > backgroundPosition >> >> > backgroundRepeat >> >> > border (with border-radius included in the property) >> >> > bpd (equivalent to block-size in css-logical-properties) >> >> > fontKerning (though without CSS's initial value, which is auto!) >> >> > ipd (equivalent to inline-size in css-logical-properties) >> >> > letterSpacing >> >> > ruby (this is done using the display property in CSS) >> >> > rubyAlign (with additional auto, end, and withBase values) >> >> > rubyPosition (with before/after names instead of over/under) >> >> > textCombine (equivalent to CSS text-combine-horizontal) >> >> > textEmphasis >> >> > textOrientation (but retaining the sidewaysLeft and sidewaysRight >> >> > values that CSS removed) >> >> > textShadow >> >> > and the following that appear not to have corresponding CSS >> >> > properties: >> >> > disparity >> >> > fontSelectionStrategy >> >> > fontShear >> >> > fontVariant (this is a property name used in CSS, but with a >> >> > different meaning!) >> >> > position (this is a property name used in CSS, but with a >> >> > different value, "center", although one that has been proposed >> >> > to be added to the CSS property) >> >> > rubyOffset >> >> > rubyOverflow >> >> > rubyOverhang >> >> > rubyOverhangClass >> >> > rubyReserve >> >> > >> >> > >> >> > My opinion on this is that this seems like a lot of divergence from >> >> > CSS. It's divergence in naming (using different names for the same >> >> > thing and the same names for different things), divergence in value >> >> > spaces, and given that everything is redefined in the TTML spec >> >> > (although often non-normatively "based on" CSS specs), almost >> >> > certainly massive divergence in semantics. >> >> > >> >> > I think TTML and CSS have largely been implemented in separate >> >> > implementations (which means that TTML has largely not been >> >> > implemented in browsers), and I don't think TTML1 was designed in a >> >> > way that would fit well in browser implementations. That's why >> >> > browsers implemented WebVTT instead. I think continuing to diverge >> >> > from CSS to this degree simply makes TTML implementation in browsers >> >> > even less likely than it already was (which was already unlikely). >> >> > >> >> > On the flip side, I don't think fixing that divergence is >> >> > particularly valuable (at least to browsers) since the communities >> >> > are already separate, and I think the chance of getting substantial >> >> > TTML implementation in browsers is low even without additional >> >> > divergence. >> >> > >> >> > -David >> >> > >> >> > -- >> >> > 𝄞 L. David Baron http://dbaron.org/ 𝄂 >> >> > 𝄢 Mozilla https://www.mozilla.org/ 𝄂 >> >> > Before I built a wall I'd ask to know >> >> > What I was walling in or walling out, >> >> > And to whom I was like to give offense. >> >> > - Robert Frost, Mending Wall (1914) >> >> >> > > >
Received on Tuesday, 13 December 2016 01:44:15 UTC